In the twenty-first century, societies need to make a wide range of measurements, from economic indicators and population trends to the times of sporting events and various standardized tests. Despite all of the varied measurement that is performed, modern societies still focus attention on the same two subjects, time and distance. In this entry, the focus will be on the measurement of distance.

Early Attempts to Measure Distance

Early civilizations used various crude instruments to measure distance, ranging from a simple pace to measuring rods and marked cords. The accuracy that was achieved with such basic devices can be astonishing. For example, the Great Pyramid of Egypt, built about 2400 B.C.E., has four base edges that are each within 0.01 percent of 751 feet in length.

Most societies developed random units of measure that became standardized over time. The Egyptians used the cubit, which varied...